The so called Internet Protocol (IP) Multimedia Subsystem (IMS) provides communication services via the Internet Protocol and IMS communication service calls are usually controlled via the Session Initiation Protocol (SIP). Some IMS communication services can be identified by means of so called IMS Communication Service Identifiers (ICSIs). Moreover, so called mobile terminations (which illustratively include modem hardware including one or more transmitters and one or more receivers for inter device communications, also referred to as MT) can be controlled by a so called terminal equipment (which illustratively includes hardware configured to interact with an end user and which includes one or more application processors and means for user interaction, also referred to as TE) through so called AT commands. AT commands exist for controlling voice calls, supplementary communication services and short messaging services as non-IMS services. However, conventionally, an AT command can control only a single voice call. Currently new AT commands are being defined by the 3rd Generation Partnership Project (3GPP) standardization group for dialing Uniform Resource Identifiers (URIs) to be used by IMS services.